It has long been recognized in the art that contact lenses must remain free of surface deposits in order to maintain their wearing comfort and optimum vision, and to reduce the potential for ocular change. However, contact lenses are susceptible to acquiring surface deposits from exogenous sources (mascara, hair spray and the like) and endogenous sources (mucous, oily secretions, protein secretions and the like). It was recognized that silicon, and particularly silicone, containing contact lenses are very vulnerable, perhaps more so than prior methyl methacrylate type contact lenses, to the acquisition of tenacious, waxy surface deposits often containing mucous and proteins which are difficult to totally remove without damaging the lenses. With the advent of fluorine containing hard contact lenses coming into commercial usage, the problems of protein and mucous deposits have lessened, however somewhat different deposits occur on lenses after use in the eye. Such deposits are oily and lipid like and are not easily removed by prior art cleaners.
As set forth in U.S. Pat. No. 4,394,179, previous hard and soft contact lens cleaning solutions have used a variety of water soluble cleaning agents, in addition to water soluble hydrating polymers in sterile homogeneous aqueous solutions. In one silicone lens cleaning material of the type set forth in U.S. Pat. No. 4,394,179, an abrasive, surface active agent and suspending agents have been used in an aqueous media to provide a good hard contact lens cleaning solution for silicone containing lenses. In another prior art cleaner, alkylphenyl polyether alcohol surfactants have been used in cleaner compositions. See for example, U.S. Pat. Nos. 4,734,222; 4,543,200; 3,884,826; 4,374,745; 4,421,665; 4,533,399; 4,622,258 and 4,678,698. Numerous other contact lens cleaning solutions have been known in the long history of contact lens use. Various surfactants and combinations of surfactants with other materials are long known for use.
However, applicants have now found that that the use of at least two surfactants in combination, one of which is an alkylphenyl polyether alcohol, along with another surfactant which is selected for its ability to remove mucous and protein deposits from hard contact lenses, is particularly desirable, especially when used in conjunction with abrasive particles.